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Quickly find whether a value is present in a C array?
...ned assembly language. I tend to take the path of least resistance - for small routines like this, I just write asm code and have a good idea how many cycles it will take to execute. You may be able to fiddle with the C code and get the compiler to generate good output, but you may end up wasting lo...
How to remove an item from an array in AngularJS scope?
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Your issue is not really with Angular, but with Array methods. The proper way to remove a particularly item from an array is with Array.splice. Also, when using ng-repeat, you have access to the special $index property, which is the current inde...
How does collections.defaultdict work?
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Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
Extracting just Month and Year separately from Pandas Datetime column
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what actually does pd.Datetimeindex do?
– JOHN
Apr 16 '18 at 5:24
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Bash empty array expansion with `set -u`
...ad. Other patterns, such as ${arr[@]-} or ${arr[@]:0}, are not safe across all major versions of Bash.
As the table below shows, the only expansion that is reliable across all modern-ish Bash versions is ${arr[@]+"${arr[@]}"} (column +"). Of note, several other expansions fail in Bash 4.2, includin...
Use of *args and **kwargs [duplicate]
...u're not sure how many arguments might be passed to your function, i.e. it allows you pass an arbitrary number of arguments to your function. For example:
>>> def print_everything(*args):
for count, thing in enumerate(args):
... print( '{0}. {1}'.format(count, thing))
...
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How to optimize for-comprehensions and loops in Scala?
...s Java. I'm revisiting some Project Euler problems in Scala that I originally tackled in Java. Specifically Problem 5: "What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?"
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Where does Scala look for implicits?
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Implicits in Scala refers to either a value that can be passed "automatically", so to speak, or a conversion from one type to another that is made automatically.
Implicit Conversion
Speaking very briefly about the latter type, if one calls a method m on an object o of a class C, and that class d...
How exactly does a generator comprehension work?
... generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one by one.
>>> my_list = [1, 3, 5, 9, 2, 6]
>>> filtered_list = [item for item in my_list i...
What is in your Mathematica tool bag? [closed]
We all know that Mathematica is great, but it also often lacks critical functionality. What kind of external packages / tools / resources do you use with Mathematica?
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